Field of the Invention
The present invention relates to an electrodeless lighting system, and in particular to an electrodeless lighting system having a cooling unit capable of cooling a radiating unit therein. 2. Description of the Prior Art
An electrodeless lighting system generates light by forming plasma by exciting light emitting materials charged inside a bulb as a vacuum state with microwave energy.
FIG. 1 is a schematic longitudinal sectional view illustrating a construction of the conventional electrodeless lighting system.
As depicted in FIG. 1, the conventional electrodeless lighting system includes a microwave generating unit 10 installed inside a housing 50 and generating microwave energy; a power supply unit 40 applying power to the microwave generating unit 10; a waveguide 20 connected to the microwave generating unit 10 and transmitting the microwave energy generated in the microwave generating unit 10; a light emitting unit 30 forming plasma 20 and generating light by being excited by the microwave energy transmitted through the waveguide 20; and a cooling fan 60 installed at a certain side of the housing 50 and cooling the microwave generating unit 10 and the power supply unit 40.
The light emitting unit 30 includes a bulb 31 in which light emitting materials are charged, a waveguide 20, a resonator 32 covering the front of the bulb 31 to cut off microwave energy and pass light generated in the bulb 31, a reflecting mirror 33 receiving the resonator 32 and intensely reflecting light generated in the bulb 31 straight and a dielectric mirror 34 passing microwave energy and reflecting light.
In the housing 50, a cooling fan 60 is received, an air suction hole 61 is formed at the lower portion corresponding to the cooling fan 60, an air path 62 is formed at the right and left portions of the air suction hole 61, and an air outlet 63 is formed at the upper portion of the housing 50 so as to correspond to the both ends of the air path 62.
The microwave generating unit 10 and the power supply unit 40 are placed between the air path 62 and the air outlet 63 and are respectively combined to the both sides of the waveguide 20.
A non-explained reference numeral 35 is an axial portion, M1 is a bulb motor rotating the bulb 31, and M2 is a fan motor rotating the cooling fan 60.
The operation of the conventional electrodeless lighting system will be described in more detail.
According to an operation signal from a control unit (not shown), the power supply unit 40 supplies power to the microwave generating unit 10, and the microwave generating unit 10 generates microwave energy having a high frequency.
While the microwave energy generated in the microwave generating unit 10 is transmitted into the resonator 32 through the waveguide 20, the light emitting materials charged inside the bulb 31 are excited and form plasma, and accordingly light is generated. The generated light lights the surroundings by being reflected by the reflecting mirror 33 and the dielectric mirror 34 toward the front.
In the meantime, while the electrodeless lighting system operates, lots of heat occurs in the microwave generating unit 10 and the power supply unit 40, etc., in particular, in the microwave generating unit 10 such as a magnetron, part of high frequency energy generated by thermal electron is not discharged but converted into heat, and accordingly an internal temperature of the housing 50 rises.
And, heat generated in the microwave generating unit 10 and the power supply unit 40, etc. may damage the internal units of the electrodeless lighting system such as the magnetron and the power supply unit 40 or cause unstableness of the system.
Accordingly, there is a need to cool the heat generated in the microwave generating unit 10 and the power supply unit 40, etc., as depicted in FIG. 1, in the conventional electrodeless lighting system, to cool heat generated in the microwave generating unit 10, etc. outer air flows into the housing 50 by operating the cooling fan 60.
However, in the conventional electrodeless lighting system, because outer air flows into the housing 50 by operating the cooling fan 60, impurities may penetrate into the housing 50, and accordingly the internal units may be damaged. Particularly, when the electrodeless lighting system is installed at the exterior, rain drops or other impurities may penetrate into the housing 50, and accordingly various parts may be damaged.
In order to solve the above-mentioned problems, it is an object of the present invention to provide an electrodeless lighting system having a cooling unit capable of being installed in a housing and efficiently cooling a microwave generating unit sealed in the housing.
In order to achieve the above-mentioned object, an electrodeless lighting system in accordance with the present invention includes a microwave generating unit for generating microwave energy; a light emitting unit connected to the microwave generating unit and emitting light by forming plasma by the microwave energy generated in the microwave generating unit; a housing having a first receiving space for receiving the microwave generating unit and sealed-combined with the light emitting unit; a heat exchanger installed at the outer surface of the microwave generating unit to absorb heat generated in the microwave generating unit; a radiator installed at the outer surface of the housing; and a heat transfer member at which one end is connected to the heat exchanger and the other end is connected to the radiator by penetrating the housing to transmit heat from the heat exchanger to the radiator.
The system further includes a fan housing having an air inlet hole for air inflow, an air discharge hole for discharging air and an air path connected to the air inlet hole and the air discharge hole and fixedly installed at the outer surface of the housing; and a fan installed in the air path to generate air flow in the air path; wherein the radiator is installed in the air path.